The aims for this core are to isolate, purify, and culture high quality human islets and make them available to investigators with qualifying grants for their ongoing research. The core also provides training and guidance to these investigators in the handling and investigation of human islets. Washington University has been one of the leading institutions in the development of islet cell transplantation as a therapy for type 1 diabetes. The dramatic improvement in the outcomes of islet cell transplantation following the introduction of the Edmonton protocol and the increase in the number of centers that have developed islet cell transplant programs, make the availability of human islets for study an even more important diabetes research priority. This Core laboratory has served and continues to serve as a local and national resource for the provision of human islets to investigators at Washington University and at other centers across the United States. The laboratory was set up as part of the Human Islet Transplant Center of Washington University. After a period of diminished clinical transplant activity, Washington University once again has an active clinical islet transplant program and has successfully performed a clinical transplant in February 2002 with additional transplants anticipated. The DRTC core laboratory benefits from being able to use the resources and infrastructure of the Human Islet Transplant Center of Washington University to provide human islets for research rather than clinical purposes to funded investigators. Under the direction of Dr. T. Mohanakumar the laboratory has continued to supply islets from humans and large animals for diabetes research. During the present funding period the function of the Core was focused towards increasing the efficiency of the isolation process, the improvement of islet purification and yield, and expansion of our islet distribution to more qualified investigators across the country. Support from the Juvenile Diabetes Research Foundation (JDRF) has supplemented these efforts allowing the laboratory to meet its goals. With the increasing importance of human islet cell transplantation, in the next funding period we plan to focus on providing human islets to investigators.